地震地磁观测与研究
地震地磁觀測與研究
지진지자관측여연구
SEISMOLOGICAL AND GEOMAGNETIC OBSERVATION AND RESEARCH
2015年
2期
31-35
,共5页
吕子强%张书建%张刚%王峰吉%于澄
呂子彊%張書建%張剛%王峰吉%于澄
려자강%장서건%장강%왕봉길%우징
走时%射线追踪%LTI%非线性插值%多种射线路径
走時%射線追蹤%LTI%非線性插值%多種射線路徑
주시%사선추종%LTI%비선성삽치%다충사선로경
travel time%ray-tracing%LTI%nonlinear interpolation%several kinds of ray paths
针对走时线性插值法(LTI)的计算精度问题,利用非线性插值替代传统的线性插值。该方法利用边界上多个节点的走时,使得插值误差减小,从而提高整体边界网格离散点走时精度,同时保留LT I所具有快速、全局性的优点。数值模拟结果表明,非线性插值算法比LT I算法精度高,可以追踪包括直达波、折射波、透射波等多种射线路径,适合速度突变模型。
針對走時線性插值法(LTI)的計算精度問題,利用非線性插值替代傳統的線性插值。該方法利用邊界上多箇節點的走時,使得插值誤差減小,從而提高整體邊界網格離散點走時精度,同時保留LT I所具有快速、全跼性的優點。數值模擬結果錶明,非線性插值算法比LT I算法精度高,可以追蹤包括直達波、摺射波、透射波等多種射線路徑,適閤速度突變模型。
침대주시선성삽치법(LTI)적계산정도문제,이용비선성삽치체대전통적선성삽치。해방법이용변계상다개절점적주시,사득삽치오차감소,종이제고정체변계망격리산점주시정도,동시보류LT I소구유쾌속、전국성적우점。수치모의결과표명,비선성삽치산법비LT I산법정도고,가이추종포괄직체파、절사파、투사파등다충사선로경,괄합속도돌변모형。
In connection with the problem of the travel time accuracy (LTI), an improved ray tracing method based on then linear travel time interpolation but using nonlinear interpolation is developed in this paper. The method takes advantage of multiple nodes on the boundary for reducing interpolation error, thus, the travel time accuracy is increased in full fi eld while the advantages of LTI method in rapid calculation and overall optimization are retained. The comparison of numerical and experimental results shows that the nonlinear interpolation algorithm is higher accuracy than the LTI algorithm and it can be used to trace several kinds of ray paths such as direct wave, refracted wave and transmitted wave for complex media.